I tried to upload a PDF document to the above website but it failed stating invalid file! I tried it on "Albums" so I may be wrong!

It is a Souvenir we published and presented to participants from overseas and SL at our Rugby Reunion held on 14th August 2015 called "Celebratory Scrum down 50 Years After" - This souvenir is about the rugby teams of 1964 &1965 winners of the Gunaratna Trophy 2 years consecutive. Warden Marc Billimoria was the Chief guest.
Captains - 1964 Juni Cader & 1965 - Rodney Murray.

I have attached this PDF I would appreciate it very much if you can advice me how I should do it or can you do it for us?